1. Field of the Invention
The present invention relates to an optical connector, and more particularly to an optical connector for mutually connecting optical fibers.
2. Related Background Art
Conventionally, in the case in which an optical connector is to be assembled at a job site, an adhesive is poured into an optical fiber inserting hole provided in a ferrule, the optical fiber is inserted therein and is fixed with the adhesive in the ferrule and the connecting end face of the optical connector is then polished. Consequently, the connecting end face of the optical connector is on the level with the tip face of the optical fiber so that the ferrules can be reliably coupled to each other. Such an example includes Japanese Patent Application Laid-Open No. 61-156207.
However, the conventional optical connector, which has the above-mentioned structure, has been the following problem. More specifically, such an optical connector requires a precise end face polishing step due to the fact that the adhesive sticks to the tip face at an adhesive assembling step to be carried out at the site. Consequently, it takes a long time to assemble the optical connector. In addition, expensive equipment is required for the precise polishing.
The present invention has been made to solve the above-mentioned problem and has an object to provide an optical connector which can shorten a time required for assembly and can be assembled easily and inexpensively.
The present invention provides an optical connector comprising a ferrule including an optical fiber, wherein a hollow portion for optical fiber protrusion is formed on a front end face of the ferrule, the optical fiber is inserted into an optical fiber positioning hole extended from an optical fiber protrusion port provided on a bottom face of the hollow portion toward an inside of the ferrule, and a tip face of the optical fiber is drawn in the hollow portion.
According to the optical connector of the present invention, the tip face of the optical fiber is not protruded from (or on the level with) the front end face of the ferrule but is drawn in the hollow portion formed on the front end face of the ferrule. In the hollow portion, accordingly, a free space exists in the vicinity of the tip face of the optical fiber. Consequently, in the case in which refuse or the like sticks to the tip face of the optical fiber, a wiping work can be considerably simplified and optical characteristics can be maintained easily and reliably. For example, the wiping work can be carried out with an applicator containing a cleaning solution. Even if the finishing precision of the tip face of the optical fiber is not increased, optical connection having a low loss can be implemented and the conventional precise polishing step can be simplified. Consequently, a time required for treating the end face can be shortened and a time required for assembling the optical connector can be reduced.
Preferably, the hollow portion has a rectangular opening window. As a consequence, a cleaning member such as an applicator can be easily inserted in the hollow portion because of the rectangular opening window.
Preferably, the hollow portion has a slit-shaped opening window. As a consequence, a cleaning member such as an applicator can be easily moved greatly along the hollow portion because of the slit-shaped opening window.
Preferably, the hollow portion has a depth of 20 xcexcm or more. As a consequence, a distance between the front end face of the ferrule and the tip face of the optical fiber (the lead-in amount of the optical fiber) can be maintained easily.
Preferably, the tip face of the optical fiber is subjected to an edge removal treatment by an electron discharge machining. As a consequence, the optical fiber can be inserted into the optical fiber positioning hole of the ferrule with the tip of the optical fiber electrically rounded. Accordingly, the optical fiber can be inserted easily. In addition, it is possible to properly prevent the tip face of the optical fiber from being chipped and to rapidly carry out the work.
Preferably, the tip face of the optical fiber is subjected to an edge removal treatment by a polishing. As a consequence, the optical fiber can be inserted easily with the tip of the optical fiber mechanically rounded. In addition, it is possible to properly prevent the tip face of the optical fiber from being chipped and to rapidly carry out the work.
Preferably, plural optical fiber protrusion ports are provided on the bottom face of the hollow portion corresponding to the number of the optical fibers. As a consequence, it is possible to roughly cut the tip portion of the optical fiber in a slight misalignment state with a predetermined alignment error even if the tip face of the optical fiber is not cut to be aligned with high precision at the previous step of inserting each optical fiber into the ferrule. As a result, the cutting work can be carried out rapidly and a time required for assembling the optical connector can be shortened.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present invention.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.